^STREPTOCOCCAL PNEUMONIA VACCINE TRIAL^


A cluster randomised trial of a pneumococcal conjugate vaccine was
conducted in the American Southwest. Residents of 19 geographic areas
were offered the Streptococcal pneumonia vaccine, and residents in 19 
other areas were offered a comparator (meningococcal) vaccine.  This
data set comes from a random subsample of the original participants, coming
from all 19 of the strep pneumo areas, and 17 of the mening areas, for a
total of 449 observations. Each line contains the number of bacterial 
pneumonia episodes experienced by one of the selected infants.

   ^randunit^      numeric, distinct for each randomised geographic area
   ^bpepisodes^    number of episodes: 0-3
   ^spnvac^        test vaccine: 0=mening comparator, 1=strep pneumo vaccine
   ^fakeid^        recoded individual participant id 

Usage for reproduction of results: 

* Table 11.4: bacterial pneumonia episodes ages 7 to 12 months
^tabulate bpepisodes spnvac^

* Table 11.5: Poisson regression with random effects
*             negative binomial regression with random effects
* 
^xtset randunit^
^xtpoisson bpepisodes spnvac, irr^
^xtnbreg bpepisodes spnvac, irr ^


^References^

Hayes RJ, Moulton LH. ^Cluster Randomised Trials, 2nd Edition.^  Chapman & Hall/CRC 2017;
Boca Raton, FL.

Moulton LH, O'Brien KL, Kohberger R et al.  Design of a group-randomized 
streptococcus pneumoniae vaccine trial.  Controlled Clinical Trials 2001; 
22: 438-452.

O'Brien KL, Moulton LH, Reid R et al. A group-randomized efficacy and safety 
trial of a seven valent conjugate pneumococcal vaccine against invasive 
pneumococcal disease among high risk American Indian children.  Lancet 2003; 
362: 355-361.

